The present invention relates generally to improvements in a stop-position limiting devices for sheet-like materials advanced along a predetermined path by transport means, and it relates more particularly to a stop-position limiting device of the above type, which includes transport or feed means which releases the transporting force from being transmitted to the advancing sheet-like material while the transporting means remains in a transporting condition.
There has long been a demand in many fields of industry for a stop-position limiting device to stop a sheet-like article in a desired position along a transporting path, by releasing the advancing force from being transmitted to a sheet-like article during its advance along such path by transporting or conveying means.
To meet this demand, there has been proposed a device, in which, as shown in FIG. 1, there is provided a friction member such as of rubber, that may be displaced between a storage or stack position A of the sheet-like articles, and a predetermined terminal position C, and the friction member is so actuated as to be swung downwards by means of a suitable swinging mechanism to contact the top surface of the uppermost sheet-like article, thereby causing the top sheet-like article to advance in the direction of the arrow, after which the friction member is swung upwards at a stop portion B so as to release a transporting force from being transmitted to the article, thereby allowing the movement of the friction member alone, to the terminal position C. Another attempt proposed as transporting means is such that the sheet-like article is carried on a belt conveyed to the stop position Y. Still another proposed mechanism operates such that a sheet-like article is transported by a roller engaging the undersurface of the sheet-like article or a pair of upper and lower rollers engaging the top face and undersurface of the sheet-like article to advance the article to a stop position. In either case, the transporting means is not provided with means for forcibly or positively stopping the sheet-like article at a predetermined position, but only releases the transporting force from being transmitted to the article. As a result, in the event that the transporting speed is increased, then the sheet-like article does not immediately stop upon release due to its momentum, but stops beyond the position where the transmission of the transporting force is released. In this case, the ultimate stop position deviates from the proper predetermined position in a range of 2 to 10 mm, when the sheet-like article is transported at a speed of 90 mm/sec. As a consequence, means for forcibly or positively stopping the sheet-like article in the precise position is dictated. The simplest positive stopping means may be an engaging shoulder portion provided on the transporting path, or a stop pin located in the transporting path. However, when a sheet-like article is further advanced from its stop position in the transporting direction, the aforesaid shoulder portion or pin is an obstacle to the advance of the sheet-like article.